Remove DesignKit package (#1886)

- Move button styles to Compound
- Rename text style to AuthenticationTextStyle as its only in the auth flow.
- Add the brand colour locally for now until its included in Compound.

* Update snapshots.

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Co-authored-by: Stefan Ceriu <stefan.ceriu@gmail.com>

ElementX/Sources/Screens/HomeScreen/View/HomeScreen.swift

@@ -232,7 +232,7 @@ struct HomeScreen: View {
                 context.send(viewAction: .verifySession)
             }
             .frame(maxWidth: .infinity)
-            .buttonStyle(.elementCapsuleProminent)
+            .buttonStyle(.compound(.primary, size: .medium))
             .accessibilityIdentifier(A11yIdentifiers.homeScreen.verificationBannerContinue)
         }
         .padding(16)